On event not working

[frankghe]

Environment

• Operating System: Win 10

• Python Version: 3.7.7

• How did you install Qgrid: pip

• Python packages: $ pip freeze or $ conda list (please include qgrid, notebook, and jupyterlab versions) jupyter-client==6.1.3 jupyter-core==4.6.3 jupyterlab==1.2.6 jupyterlab-server==1.1.4 matplotlib==3.1.3 notebook==6.0.3 pandas==1.0.3 qgrid==1.3.1

• Jupyter lab packages (if applicable): $ jupyter labextension list JupyterLab v1.2.6 Known labextensions: app dir: C:\Users\fghenass\Anaconda3\envs\realestate\share\jupyter\lab @8080labs/qgrid v1.1.1 enabled ok @jupyter-widgets/jupyterlab-manager v1.1.0 enabled ok @jupyterlab/debugger v0.1.2 enabled ok qgrid2 v1.1.3 enabled ok

Uninstalled core extensions: @8080labs/qgrid

Description of Issue

Methods qgrid.on() and QgridWidget.on() have no effect, ie. handler is registered, but never called.

Reproduction Steps

Code below can be used to reproduce problem:

import pandas as pd import qgrid df = pd.DataFrame({'col1': [1, 2], 'col2': [3, 4]}) grid = qgrid.show_grid(df, show_toolbar=True) grid count=0 def record_change(event, widget): count +=1 print('handler fired') grid.on(names='cell_edited',handler=record_change)

Note: other events also do not fire the event, nor

I also tried to use the example provided in the following page, with same result (graph not updated in this case): https://github.com/quantopian/qgrid-notebooks/blob/master/events.ipynb

What steps have you taken to resolve this already?

...

Anything else?

...

[fdobad]

You forgot the global statement before modifying a local variable

count=0
def record_change(event, widget):
    global count
    count +=1
    print('handler fired')

grid.on(names='cell_edited',handler=record_change)
grid

Avoid global like the plague:

class QgridCounter():

    def record_change(self, event, grid_widget):
        self.count +=1
        print('handler fired %d times'%self.count)

    def __init__(self):
        self.df = pd.DataFrame({'col1': [1, 2], 'col2': [3, 4]})
        self.grid_widget = qgrid.show_grid(self.df, show_toolbar=True)
        self.grid_widget.on(names='cell_edited',handler=self.record_change)
        self.count = 0

    def disp(self):
        display(self.grid_widget)

QgridCounter().disp()